The field of the disclosure relates generally to dry etching, and more specifically, to methods and systems for dry etching of photodetectors.
Generally, photodetectors are used in a variety of camera systems to detect light. The photodetectors include an array of sensors or Focal Plane Array (FPA) that is formed by an array of sensors electrically insulated from one another. One form of insulating the sensors from one another is through etching in which material is removed to create trenches between sensors. A wet etch process is an isotropic process whereby a solution (e.g., acid or base) is used to remove material. A dry etch process is an anisotropic process in which material is removed after exposure to a plasma. In some known wet etch processes, the acid solution etches laterally in the trenches leading to a reduction in optical response per pixel (i.e., loss of fill factor) and in some known dry etching processes, organic compounds are formed during deep etchings that reduce optical response per pixel or increase the dark current.